In current practice the automotive manufacturer produces commercial bodies only of the types that can be sold in such large quantities as to warrant mass production. Special body types in limited numbers or orders for larger numbers of highly specialized bodies are usually filled by independent vehicle body builders. Examples of such types are those used by the military and postal services. The chassis manufacturer supplies the running gear, steering assembly, and the cab. The body manufacturer obtains an order or contract to build and install a specified body for the designated chassis. It is therefore a substantial problem to connect the forward portion of the body to the already fabricated cab in a satisfactory manner. Not only must this section be weather tight, but it must also have maximum visibility, low cost, and ease of installation. Curved glass sections are expensive and unless large volume production is needed, the cost may be prohibitive. In addition, it is important that limited movement between the body and the cab sections does not rupture the glass nor the seal.